Plunger and die mechanism for forming trays



July 21, 1970 w. WALDBAUER ET A1.v 3,521,536

PLUNGER AND DIE MECHANISM FOR FORMING TRAYS Filed Sept. 25, 1965 '4 Sheets-Sheet l llll lllllulllllllll lllulllllll llnlll l July 21,1970 .W.WALDBAUER- ETAl- 3, 21,536.

PLUNGER AND DIE MECHQNISM FOR FORMING TRAYS Filed Sept. za. 1965 4 Sheets-Sheet 2 July 21, 1970 Filed Sept. 23. 1965 W.WALDBAUER E PLUNGER AND DIE MECHANISM FOR FORMING TRAYS 4 SheetS -Sheet 3 lhv htors Mum PLUNGER AND DIE MECHANISM FOR resume TRAYS July 21,1970 w; WALDBAUER any Filed Sept.

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INVENTOR WILHELM WALDBAUER ATT. 15,.

United States Patent PLUNGER AND DIE MECHANISM FOR FORMING TRAYS Wilhelm Waldbauer, Stuttgart-Lederburg, Richard Osterle, Stuttgart-Wauger, and Heinz Hinderer, Stuttgart, Germany, assignors to TheFinn Industries, Chicago, 111., a corporation of Delaware Filed Sept. 23, 1965, Ser. No. 505,605 Int. Cl. B31b 1/44; B21d 5/02, 51/00 US. Cl. 93- 51 ABSTRACT OF THE DISCLOSURE Apparatus for assembling or erecting a folded box or tray from a cardboard blank or the like wherein the blank includes a generally rectangular bottom wall, opposed side and end walls hingedly connected to the periphery of the bottom wall along fold lines and locking means at the four corners or side juncture of the side and end walls for securing the side and end walls in an erected position. The bottom wall may be mounted on a rectangular base of larger width and length to define a peripheral rim portion. The folded or erected member may be utilized as a lid or body of a container or box. The box forming apparatus, also referred to herein as a plunger and die mechanism, includes a frame, a die having opposing stop members adapted to engage the corresponding margins of the base of the blank, a pair of opposed guide members operable when a blank is positioned in the die by the plunger to pivot one pair of opposed walls of the blank, for example, the end walls to a predetermined desired angle, and actuating means for moving at least one of the guides. The box forming apparatus further includes a jaw pivotally mounted at each of the other pair of opposed margins of the die, linkage means interconnecting the movable guide with said jaws thereby to fold the side walls to an erected position and'pivotal folding members to fold the end wall panel extensions to a position overlying or confronting the end walls. The apparatus is characterized by an arrangement whereby when the plunger is operated to position a blank in the die, the side and end walls are partially 7 Claims erected and when the movable guide is actuated the end walls are erected to the desired angle, the corner extensions are folded, the opposing side walls are erected by the jaws and the folding means folds in the extension panels to lock the box member in its erected position.

The present invention relates to apparatus for forming trays or the like from a blank sheet material made of cardboard.

The box, tray or the like which the apparatus of the present invention is designed to assembly from a substantially flat blank, comprises a generally rectangular bottom wall, and upstanding opposed side and end walls which are spaced inwardly from the edge of the base on which the bottom wall is mounted to define a peripherally extending rim portion and locking means for securing the side and end walls in the upstanding or erected position. For example, the locking means at the corners of an erected box may comprise simple interengaging tongues or substantially rectangular panel extensions of the side and end walls which are creased diagonally to provide triangular pleated extensions. The extending panel sections are folded along the diagonal crease to support the side and end walls or panels in an erected position by any suitable means. For example, the side walls may be provided with panel segments or extensions that bend along a crease line and are adapted to be bent over and secured in face to face relation with the side walls by an adhesive, such panel extensions having cutouts adapted to receive nibs or tabs projecting from the ends of the panel exten- 3,521,536 Patented July 21, 1970 sions of the end walls to lock the walls in their upright position.

With the foregoing in mind, an object of the present invention is to provide a novel plunger and die mechanism for erecting. boxes of the above type which is extremely simple to operate, is comprised of comparatively few parts and is fully effective for the purposes intended.

According to one feature, the present invention consists in a plunger and die mechanism for erecting a tray of the kind described comprising a stop projecting 'across the mouth of the die at each of two opposite walls thereof and adapted to engage the corresponding margins of the base of the tray, a guide at each of said opposite walls operable when a blank is forced into the said die by the plunger, to bend up one pair of opposite tray walls to the desired angle, means for moving at least one of said guides to render them operable, a jaw pivotally mounted at each of the other pair of opposite walls of the die, linkage interconnecting said movable guide with said jaws, and means operated by movement of the guide for folding in the extending panels of said one pair of walls, the arrangement being such that the plunger is operated to force a blank into the die partly to bend up the walls whereupon the movable guide is moved to correctly position the blank, to bend up completely one pair of walls of the tray to the desired angle, to bend the corner extensions, through the linkage to cause the jaws to bend up the other pair of opposite walls, and to operate the folding means to fold in the extending panels to lock the tray in its erected position.

If desired, the movable die may be mounted on a reciprocating member slideable in a fixed way of the machine and each of the jaws may comprise a rail secured to one end of a pivotally mounted lever, the other end engaging in a cam slot in the reciprocating member whereby movement of the guide to fold the opposed end Walls of the tray or box acts to pivot the rail and thus simultaneously folds up the other opposed pair of side walls. Additionally, the guides may be provided with re cesses to receive the rim of the base wherein the combined depth of the recesses of the opposed pair of guides is approximately equal to twice the width of the rim.

The basic apparatus may be modified to accommodate other types of boxes. For example if desired, both guides may be made movable simultaneously and interconnected so as to be actuated towards and away from each other an equal distance. The guides may also be disposed at right angles to the base of the box and the jaws may lie at the same angle to the base when in their wall engaging position, thus providing a box having vertical walls. Alternatively, the guides may lie at an acute angle and the jaws may lie at the same acute angle to the base of the box and in their wall erecting position, thus providing a box having sloping side and end walls.

These and other objects of the present invention and various features and details of the operation and construction of a box forming apparatus in accordance with the present invention are hereinafter more fully set forth with reference to the accompanying drawings, wherein:

FIG. 1 is a plan of a die;

FIG. 2 is a view on line 22 of FIG. 1;

FIG. 3 is a view on line 3-3 of FIG. 1;

FIG. 4 corresponds to FIG. 1 but shows the guide 16 on its tray walls bending condition;

FIG. 5 is a view on line 5-5 of FIG. 4;

FIG. 6 is a vieW on line 6-6 of FIG. 4;

FIG. 7 is a view on line 77 of FIG. 4;

FIG. 8 is a view corresponding to FIG. 5 but showing guides suitable for providing a sloping walled tray;

FIG. 9 is a View on the line 9-9 of FIG. 8;

FIG. 10 is a plan view of one type of box blank which may be formed into a box or the like by box forming apparatus in accordance with the present invention;

FIGS. 11, 12, and 13 are perspective views, each view showing a half of the blank in partially erected positions; and

FIG. 14 is a fragmentary perspective view showing a corner construction of the assembled or erected box.

Referring now to the drawings, and particularly to FIGS. 1-7 thereof, there is shown a box forming apparatus for erecting box blanks in accordance with the present invention, also referred to herein as plunger and die mechanism. The embodiment of the invention is particularly adapted for erecting boxes formed from a blank of sheet material.

FIGS. -14 inclusive show an example of a blank and a box or the like which the box forming apparatus of the present invention is designed to form. It is noted that even though a particular blank and box configuration is illustrated, the box forming apparatus of the present invention may accommodate other forms of blanks and boxes. The blank, generally designated by the letter B, comprises a generally rectangular wall 100 forming a top or bottom, depending on whether the erected assembly is used as a lid, tray, or box, a pair of opposed end walls 102a and 102k connected along fold lines 104a and 104b to the wall 100, and a pair of side walls 106a and 1061: connected to the wall 100 along parallel fold lines 108a and 108b. In the present instance the wall 100 is mounted on a base 110 of generally rectangular configuration of a greater width and length than the wall 100 to define a peripherally extending rim R. The end wals are provided with generally rectangular extension panels 112a and 1121) connected along fold lines 114a and 11417 to the end walls, the panel extensions having flaps 116a and 11612. The side walls 106a and 106b also having panel extensions 120a and 120k having projecting tab members 122a and 1221; at opposite ends, and being smaller in length than the side walls to provide in the assembled box recesses or slots 125 to receive locking nibs 127 extending from opposite side edges of the end wall panel extensions 112a and 112b, The blank B also includes corner extension segments 130 which are creased diagonally as at 132.

In assembling this blank, the side panel extensions 120a and 120b may be manually bent along the fold line into overlying relation with the side walls 106a and 160b and secured in this position by means of an adhesive as illustrated in FIG. 11. The side and end walls are then pivoted or bent along their respective fold lines as shown in FIG. 11 whereby the corner extension segments 130a and 13012 are folded inwardly to a position where they confront and overlie the end walls when the side and end walls are disposed perpendicular to the base. In this position, the end panel extensions 112a and 112k and flap at each end of the box are. folded inwardly to the position shown in FIG. 13 whereby when the end panel extension is folded completely to overlie the end wall, the tongue 127 engages in the recess 125 to maintain the box in an erected position.

The apparatus comprises framework of generally rectangular configuration including frame members 11, 12, 13 and 14 having a pair of closed spaced apart, fixed stop members 17 and 18 that project across the mouth of the die and are engageable by the rim of the blank when the blank is positioned therein in the manner shown in FIGS. 1 and 2. The stop 17 mounts a guide member having a guide face 15a extending across the width of the die opening disposed at right angles to a plane X-X through the stop members in which the base of the blank lies when positioned therein. The apparatus also includes a movable guide member 16- having a guide face 16a confronting the guide face 15a of the fixed guide 15 also disposed at right angles to the plane XX. The guide member 16, as illustrated, extends across the width of the die opening and is mounted on rods 19 and 20 interconnected by a bar 23,

the rods 19 and 20 being adapted for reciprocating movement in guideways 21 and 22 mounted on the frame 14. The actuating means for the rods 19 and 20 includes a cam device 34 connecting the bar 23 to a push rod 35. By this arrangement when a partially formed blank has been positioned in the die openingby means of plunger 2, the rod 35 is actuated by suitable means to the left with respect to FIG. 2 to securely position the blank in the die opening and to fold the end walls 102a and 102b of the blank to a fully erected position.

The side walls 106a and 106b of the box are folded to an erected position by means of a pair of elongated bar members 30 and 31 having jaws 32 and 33 respectively which engage through slotted openings in frame members 11 and 12 and are adapted for pivotal movement to fold the side walls in the manner shown by the double arrows in FIG. 4.

The bar members 30 and 31 are pivotable upon actuation of the guide member 16 and to this end cam slots 26 and 27 operating on spherical heads of levers 28 and 29 whereby, as the cam plates 24 and 25 move backwards and forwards with the guide member 16 they rock or pivot the bars 30 and 31 mounted on the levers 28 and 29 between the positions indicated in FIGS. 3 and 6.

As best illustrated in FIGS. 2 and 5, the guide members 15 and 16 are provided with elongated recesses 15b and 16b of a depth approximately equal to the width of the projecting rim R of the box so that when the guide member is actuated to the left with respect to FIG. 2, to the position shown in FIG. 5, the blank is correctly positioned in the die and the sidewalls and end walls of the blank are folded at right angles to the base, the guide faces 15a and 16a being disposed at right angles to the base of the blank. Pivotally mounted folding members 36 and 37 are provided to fold the end panel extensions 112a and 11212 of the end walls to overlapping relation after the blank has been assembled or erected to the partially folded position shown in FIG. 2. 1

Considering now the operation of the box forming apparatus of the present invention, fiat die blanks B of the type described above are fed one at a time bythe plunger 2 into the die opening so that the rim R engages the stops 17 and 18.

As illustrated this acts partly to fold up the side and end walls and the triangular pleated corner extension panels 130. The push rod 35 is then moved inwardly, for example, by closing the switch of an electric motor actuator and this serves to position the blank correctly, the guide moving the blank so that the end edges of the rim R engage in the recessed gaps in the guide members 15 and 16 (see FIG. 5). During movement of the blank in this manner, the side and end walls are folded to a vertical position relative to the base and the corner extension panels 130 are folded along the diagonal crease line 132 in the manner shown in FIG. 11. When the guide member 16 reaches the end of its inward stroke, the folders 36 and 37 are automatically operated, for example, by means of a switch engaged by the guide member whereby the end panel extensions 112a and 11% are folded in face to face relation with the end walls thereby embracing the corner pleats and engaging the locking nib 127 in the cut-out of the side extension panels of the side walls. (See FIGS. 13 and 14.) It is noted that the side extension panels of the side walls may be folded in overlapping relation by hand or automatically.

The guide member then is returned to its initial position for a distance equal to twice the width of a rim extension and the succeeding blank forces the formed box through the die opening. If desired a light spring may be incorporated in the guide member 15 to eject the formed box clear of the stop member 17.

The apparatus may accommodate box blanks of varying sizes and to this end the cam 34 provides means for adjusting the guide member 16. For example, by offsetting the pivotal connection of the push rod 35 with respect to the center point of the rotatable cam 34, the initial position of the guide member may be altered. Additionally, instead of making only the guide member 16 movable, both guide members 15 and 16 may be actuatable towards one another, for example, by means of a linkage interconnecting the guide member 15 to the guide member 16. In this case, of course, each guide member will be adapted for movement a distance equal to the width of a box rim.

There is illustrated in FIGS. 8 and 9 a modified form of the apparatus described above. This apparatus is generally similar in overall operation and detail. However, in the present case the guide faces of the guide members 15 and 16' and the panel engaging surfaces of the jaws 32' and 33 are inclined so as to provide a box having sloping side and end walls. In this case, the stops engage at the margins at the face of the box.

While particular embodiments of the present invention have been illustrated and described herein, it is not intended to limit the invention and changes and modifications may be made within the scope of the following claims.

We claim:

1. A box forming apparatus for forming a box from a blank, the box having a central panel, opposed pairs of walls connected to the central panel along fold lines, locking means at the juncture of the walls and at least one pair of the opposing walls having panel extensions connected to the walls on a fold line, the apparatus comprising a main frame, a die member, a stop projecting across the mouth of the die, a plunger for positioning a box blank in the die, a pair of spaced apart guide members at opposite ends of the frame, actuating means for actuating said guide members relative to one another to fold one pair of opposed walls of the blank to a predetermined angle relative to the central panel, a pair of jaw members pivotally mounted to said frame, linkage means interconnecting one of said movable guide members with said jaws whereby actuation of said guide members effects pivotal movement of said jaws to fold the other pair of walls to an erected position, a pair of folding members and means operatively connecting said folding members to said movable guide member for folding the extension panels of said one pair of walls of the blank into overlying, confronting relation to said one pair of walls.

2. Box forming apparatus as claimed in claim 1 wherein said movable guide member is mounted on a reciprocating member slidable in fixed Ways of the frame.

3. Box forming apparatus as claimed in claim 2 wherein each of the jaws comprises a bar secured to one end of a pivotally mounted lever, the other end of said bar engaging a cam slot in the reciprocating member whereby movement of said guide member in a direction to fold opposing walls of the box pivots each to fold the sidewalls of the box,

4. A box forming apparatus for forming a box from a blank, the box having a central panel, opposed pairs of walls connected to the central panel along fold lines,

locking means at the juncture of the walls and at least one pair of the opposing walls having panel extensions connected to the walls on a fold line, the apparatus comprising a main frame, a die member, a stop projecting across the mouth of the die, a plunger for positioning a box blank in the die, a pair of spaced apart guide members at opposite ends of the frame, actuating means for actuating said guide members relative to one another to fold one pair of opposed walls of the blank to a predetermined angle relative to the central panel, a pair of jaw members pivotally mounted to said frame, linkage means interconnecting one of said movable guide members with said jaws whereby actuation of said guide members effects pivotal movement of said jaws to fold the other pair of walls to an erected position, a pair of folding members, means operatively connecting said folding members to said movable guide member for folding the extension panels of said one pair of walls of the blank into overlying, confronting relation to said one pair of Walls, and means defining elongated recesses in each of said guide members providing pockets to receive the rim of the base, the combined depth of said pockets being equal to twice the width of the rim.

5. Box forming apparatus as claimed in claim 1 including means connecting each of said guide members for movement relative to one another an equal distance.

6. Box forming apparatus as claimed in claim 1 wherein each of said guide members is provided with a guide face adapted to engage the end walls of the box disposed at right angles to the base of the box and the jaws are provided with surfaces disposed perpendicular to the base when in their side wall engaging position, thus providing an erected tray having vertical side walls.

7. Box forming apparatus as claimed in claim 1, wherein the guide faces of the guide members are disposed at an acute angle to the base of the box and the side wall engaging surfaces of the jaws are disposed at a similar angle thus providing an erected box having inwardly sloped side and end walls.

References Cited UNITED STATES PATENTS 2,852,988 9/1958 Bowman 9351 2,865,263 12/1958 Strand 9351 3,086,427 4/1963 Waldbauer et al 9351 3,102,456 9/1963 Bailey 9351 X BERNARD STICKNEY, Primary Examiner US. Cl. X.R.

Patent No. 3,521,536 Dated July 21, 1970 Inventor(s) WILHEIM WALDBAUEK, RICHARD OS'I'ERLE and HEINZ HINDERER It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 5, line 55; "fold opposing walls of the box pivots each to fold the" should read --fold opposing walls of the box pivots each rail to fold the-- Amt:

Edward H. 11min, Iim B. m. Atmting Officer ullion!!! or Pam.

FORM PO10 0( I USCOMM-DC 60376-P69 U Sv GDVIINIENY PRINYING OFFICE: 10! 0-3C-SSI 

